Method of igniting liquid fuel.



A. DOBLE. METHODVOF IGNITfN'G LIQUID- FUEL.

APPLICATION FILE'D MAY 12| 19|?.

Patented Mar. 26', 1918.

2 SHEETS-SHEET l.

A. DOBLE.

METHOD OF IGNITING LIQEPID FUEL.

APPLICATION FILED MAY l2. i917.

Patented Mar. 26 1918.

2 lSHEETS--SHEET 2.

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nnrrnn sauras @Attentat @nur 'ABNER DBLE, 0F DETROT, MICHGAN, ASSGNOR TO GENERAL ENGHI'EEEE'NG" lltl PANY, 0F DETROIT, MIICHGN, A CORPORATUN 0F JIICHIGN.

METHUD 0F Iii-NEMEN@ LEQUD EIUETJ.

Specification of Letters latent.

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application nea nay it, 1er?. seran no. reason.

To all LU/tom it may concern.

Be it known that l, ABNER Donne, a citizen of the United States of America, and resident of Detroit, Wayne-county, Michi-y gan, have invented a certain new .and useful improvement in Methods of lgniting `Liquid Fuel, of which the following is a specification.

My invention relates to the art of burning Ywherein the elimination oit the annoyance and delay of pre-vaporization of the fuel perature condition and extremely high temperatures obtained for the generation of steam, by the atomization process of iinely dividing or pulverizing the liquid and mixing it with proper amount ot air to support combustion and confining the combustion in a closed refractory chamber which attains an intense incandescent tempera-ture.. hydrocarbon at normal temperatures may be atomized or broken up and mixed with the proper proportion of air to complete com. bustion within said chamber, or the air which supports combustion may be used as the atomizing agency for finely dividing the hydrocarbon and projecting it into the combustion chamber. ln any event, however, there must be a sufficient proportion of air in the mixture to complete combustion in the combustion chamber, Without any smoke or soot whatever else'the very advantage attendant upon a utilization'ol'the atomizing method in asteam-driven automobile power plant is lost. As before mentioned, l have found in practice that a mixture of the atomized fuel and air burned in a chamber in the The 'f manner above mentioned can be completely consumed without soot and smoke, but such a mixture (which ll will refer to fory convenience as the main or completely comhusv tible mixture), has a relatively excessive proportion of air and a relatively small proportion of atomized fuel. ln other words, relatively speaking, this mixture is rich in air and lean in hydrocarbon.

rllhe extreme desirability in an automobile e power plant, of instantaneous initiation oit combustion of fuel, and the use ot an electric spark for this purpose, is at once olovious, but a mixture such as l have just described will not ignite at normal tempera# f ture by means of an electric spark, although, after having been properly ignited, it will sustain complete combustion in said chamher. So :tar as it' am. able to ascertaimthe failure ot this mixture to ignite lrom a spark is due to the fact that a spark ot practical proportions, although intensely hot, is

comparatively small in volume, and in such a relatively lean mixture the particles oi fuel are separated in a comparatively large volume of air to such an extent that the air ab sorbs the heat and prevents the transmission of heat to adjacent particles from those ignited. Furthermore, it in addition 'the hody of mixture is moving at comparatively high velocity, the particles do not remain in the small zone ot heat ot the spark long enough to become ignitedn i l have discovered, however, that a mixn ture of linely divided hydrocarbon and air at the normal atmospheric temperatures can readily be instantly ignited by an electric spark if the mixture is excessive or rich in hydrocarbon and lean inx air, but on the other hand, a mixture of this character is not completely combustible, there being insanicient air therein to entirely 'orv completely consume `the hydrocarbon, even under the most favorable conditions, hence such a mixture which for convenience of reference 4l will term the auxiliary or incompletely lli gli

develop the temperature necessary in an automobile power plant. `As betorementioned, however, this mixture willl readily and rei p'eatedlyignite by an electric spark because,

so tar as 'l am ableto ascertain, the particles of hydrocarbon are relatively close together and not diluted with air to any great extent,

hence the heat generated by the spark, al.

though small in volume, is readily dissipated and absorbed into the fuel particles instead of air, and the particles in the immediate heat zone ignite and readily transmit their flame to the adjacent particles, thus instantly building up a body of flamethroughout the mixture. Now, by utilizing the characteristics of both of these mixtures, ll am able to bring about, without pre-vaporization, the instantaneous ignition of a completely combustiblemixture at normal temperature for the sustained or continued production of heat, byv means of an electric spark, which result, in the case of an automobile power plant, leaves nothing for the operator to do but to start the sparking and mixture forming mechanisms, and which in practice amounts to nothing more than the operation of an electric switch, n

ll accomplish these results by producing a rich mixture by atomizing hydrocarbon and air, igniting the same bya spark, then producing a mixture suifciently rich in a1r to bring about complete combustion, the latter mixture being ignited by the flame of the rst mixture.

rl`he fuel ignition and burning apparatus which l disclose in the accompanying drawings illustrates vthe preferred .manner in which my improved method is carried into ed'ect in a steam-driven automobile power' The main or completely combustible mix-- ture, to which I have referred, is in the presentstructure produced by a blower A and Venturi atomizers B, of .which there are two. placed side by side, although for the purposes of my invention one atomizer is sufficient. rFhe two atomizers in this' case roduce two streams or currents ofmixture. hesev atomizers are formed by the tubular Venturi passages formed in the casting or member C, and the nozzles D for the liquid fuel. The Venturi passages are tapered, being vlarger in diameterat their inner discharge ends, and the fuel nozzles Dare positioned in the throats thereof'in-uprght relation, their ends reaching to about the cenv t5 ter of the Venturi throats. The blower A masones is mounted at the ends of the atomizer passages with its outlet A directly connected with the said passages, the blower outlet being divided into tw passages to register with the two Venturipassages. rlhe blower may, of course, be of any suitable type for the purpose, but preferably is of the socalled volume type! consisting of a casing and a fan or blade wheel rotatable therein,

and capable of moving a large constant volume 'of air. It is preferably driven by a small electric motor A?, one terminal of which is connected by the conductor E with a source of current suchtas an electric batterr F. The other terminals of both battery an motor are grounded. A switch G is provided in this circuit by which' the operator may control the operation of the motor as desired. The blower provides a constant blast or current of air through eachof the Venturi passages, which in accordance with the principles of atomization draws thc liquid fuel from the nozzles and pulverizes or finely divides and mixes with the fuel, thus producing a spray of mixture from each 90 of the nozzles which is projected from said atomizers. ln this structure the mixture thus produced is projected into a closed combustion chamber G, the walls of which are formed of refractory material capable of being rendered incandescent by the heat of combustion. This chamber has side walls Gr and a bottom wall G2, and the corners and angles are well rounded so as to give the combustion a general bowl shape. rlhe Venturi member extends substantially horizontally in position to project the main mixture into said chamber, and when the mixture is ignited two flames sweep across the combustion chamber to the opposite wall "thereof, where they meet with a curved baffle '(not'. shown) by which the streams are deflected orturned backhorizontally upon themselves, thus producing a violent swirling of the fl'ame within the chamber. The 110 flames are confined by the walls and bottom of the chamber which with great rapidity become highly incandescent and thus create Aan intense uniform zone of heat within the chamber, which brings about la complete combustion of the hydrocarbon;A rll`he atomizer and blower are so proportioned that the main mixture from these atomizers is suplied with copious quantities of air from the lower, sufficient` to support the complete combustion of the fuel within the chamber'.

In consequence, the mixture is relatively dilute and cannot be directly ignited from the small volume of llame froman electric spark. ll therefore produce the auxiliary mixture which will ignite `by the spark and effect the ignition of ther main mixture by the flame of the ignited auxiliary mixture.

In the structure shown, a long chamber J is formed in the member C and positioned un- M0 maaaae derneath and between the main Venturi passages. This chamber is closed exceptat its inner end, part of the walls of the end portions of the main Venturi passages being cut Vaway to provide direct communication between the auxiliary chamber and the Venturi passages at their inner discharge ends. Tn addition, the' structure has an upturned lip K across the ends of the Venturi passages and the auxiliary chamber so as to divertvor deflect the auxiliary Hame'upwardly directly in the path of the main mixture projected from the nozzles whereby t immediately ignite said mixture. At the closed end of the auxiliary chamber there is a fuel nozzle L fed from the same source of hydrocarbon at the same normal temperature as the main nozzles being connected with the same manifold L which is positioned and fastened on the under side of the member C. Adjacent this fuel nozzle L, in fact formed in the same member, is an air passage L2 having its upper end L3 positioned at an angle to the 'end of iid the nozzle passage L, so as to form an air nozzle in atomizing relation to the fuel nozzle L. The air nozzle is connected with a source of compressed air, such as an air tank (not shown)l yunder a few pounds pressure, and vwhen the air is owing the fuel is drawn from nozzle L and atomizes orinely divides it, projecting the mixture through the auxiliary chamber to the inner end thereof. A relatively small proportion of air is thus mixed with the pulyerized fuel but just enough to support combustion to some extent, the mixture being very rich in fuel and in such condition that it will readily ignite with .a spark. ThisA mixture, rich in fuel, fills the'chamber and provides a very j fertile-zone or field for the heat of the spark to ignite and 'accelerate combustion in the mixture. The fuel and mixture are of fcourse atlnormal, that"is, atmosphericl temperature. The spark in the structure shown is, producedat the terminals "N ofthe plug N', which .terminals are positioned directly in thelpathbf the' spray of rich ycold'mixture from the auxiliary atomizer. Having s thus initiated .combustion in the auxiliary` mixture, which in practice is instantaneous,

,a flame y,ofsubstantial proportions is pro duced `which is emitted from theinner end dit of thelauxiliary chamber J iii-tothe pathof the main-mixture and ignitesjthfemain4 mix? ture as before described. The fduratioiiof the auxiliary flame need be but momentary because in practice, the matter of time from the initiation of the spark until the main streams of mixture become ignited ispractically instantaneous. However, the yplume of auxiliary mixture i is relatively smaller than the volume of main mixture and does not, when ignited, produce anyl appreciable volume of smoke, hence if it is continued for purpose.

any length of time the smoke is not notice-v able, particularly since the smoke is carried into the combustion chamber by the main mixture and. there consumed. The electrical equipment-for the production of the spark may be of any suitable type for the ln thedrawings I illustrate an ordinary spark coil, the secondary winding S of which is connected with the spark plug in a grounded .circuit S', while the primary winding P is in a grounded circuit P which includes, the battery l?. This circuit also includes the suitable switch G by which the operator may control the spark as and when desired. The combustion chamber is in practice closed at its upper end by a steam generator R, the lower ends of the evaporating units of which are indicated, so that the heat produced by the main-flame of burning fuel is instantly available for the generation i of steam.

vThe apparatus herein disclosed for carrying out my improved method constitutes subject-matter of my co-peiiding application Serial No. 168,801, filed May 12, 1917.

T claim v 1. The method of initiating combustion in a mixture at normal temperature of finely divided li'qui-d hydrocarbon andl air of such proportion of air as to insure complete combustion of said fuel, which consists in rstv igniting relation to said mixture a second mixture 4of said finely divided hydrocarbon and insufficient air to support complete combustion, and initiating combustion in said incompletely combustible mixture atnormal Miti temperature `by means of' an electric spark. 3.. The method of igniting heavy hydroycarbori/sy"which are non-volatile or. substantially l lnon-volatile at normal tei'iiperatiires .which consists in maintaining a spra rich mixture lof air` and said' hydrocarbon iia atomizfed but incompletely combustible condition,i`gniting saidvmixture by means .of an electric ',"sparlnto establish a Haine, maintaining al mixturesof said atomized hydrocarbon and sufficient air to completely combust said hydrocarbon, and directing the flame of said spark ignited flame into said completely combustibll mixture. f

4. The method herein described of igniting heavy hydrocarbon oils while cold, consisting of maintaining a main blast of comminuted hydrocarbon highlyediluted with airto a sulicient degree to'insure complete combustionof the hydrocarbon, maintainv ing adjacent thereto an auxiliary blast of air commingled With an excess of comminuted hydrocarbon, igniting said auxiliary richer blast by an electric spark, and directing the flame of the burning auxiliary blast into the main blast to thereby ignite' the same.

5. rlhe method of igniting heavy hydrocarbons which are non-Volatile or substantially non-Volatile at normal temperatures, which consists in maintaining a, spray of rich 'mixture of air and said hydrocarbon in atomized but incompletely combustible condition, igniting said mixture by means of an electric spark to establish a fiame, maintaining a mixture of said atomized hydrocarbon and suiiicient air to completely combust said hydrocarbon, directing the ame of said spark ignited flame into said completely combustible mixture, and causing said combustible mixture so ignited to sweep over and circulate about a broad expanse` of a material adapted to become Laeoas -highly incandescent thereby insuring complete combustion.

6. The method of initiating combustion in a mixture of sprayed kerosene and air incapable at normal temperature of ignition Iby an electric spark, Which consists in igniting by means of an electric spark a mixture of sprayed kerosene and air at normal temperature capable of ignition by said spark,

and igniting said rst mixture by the flame of said spark-ignited mixture.

7. The method of initiating combustion in a mixture of sprayed non-volatile hydro- ABNER DOBLE. 

